Featured Research

Manipulating the metabolic process in cells may compensate for defects that can shorten cell life

Date:

April 11, 2014

Source:

University of Alberta Faculty of Medicine & Dentistry

Summary:

Mitochondria produce energy for cells through oxidative metabolism, but the process produces toxic byproducts that can accumulate and cause defects in the cell's mitochondria. These defects, in turn, affect the cell's ability to generate energy and can potentially lead to cell death and are associated with aging and various neurological diseases. Researchers have examined how dietary changes at the cell level can affect cell health.

Share This

UAlberta researchers are taking a closer look at how two metabolic pathways interact to increase the lifespan of cells with mitochondrial defects. Magnus Friis (PhD '10) is the lead author of the study, which was published online on April 10 and will be published in the April 24 issue of Cell Reports.

Related Articles

Mitochondria produce energy for cells through oxidative metabolism, but the process produces toxic byproducts that can accumulate and cause defects in the cell's mitochondria. These defects, in turn, affect the cell's ability to generate energy and can potentially lead to cell death and are associated with aging and various neurological diseases.

Friis, a postdoctoral fellow in Mike Schultz's biochemistry lab, examined how dietary changes at the cell level can affect cell health. He exposed normal and defective yeast cells to two different energy sources: glucose, the preferred sugar of cells, and raffinose, a natural sugar found in vegetables and whole grains.

"[The dietary intervention] is a general shift in what we're feeding the cells to get them to do something different with their whole nutrient metabolism," Friis noted. "There are signaling pathways that allow a cell to sense its environment and co-ordinate events to allow the cell to adapt to what's going on. In this case, [cells are responding to] which nutrients are available."

Friis and Schultz examined two nutrient signaling pathways called the AMPK pathway and the retrograde response. AMPK responds to energy deficits in the cell by down-regulating energy consuming processes, which are often associated with cell growth, and up-regulating energy producing processes. The retrograde response pathway is specific to the yeast used in the study and supplies key amino acids to the cell by changing the metabolic process of the mitochondria.

"We looked at the effect activating both pathways had on maintenance of cellular viability in what's called a chronological aging experiment," Friis said. "Even when they had defective mitochondria, the cells with the retrograde response and AMPK simultaneously activated during growth were able to live as long as cells with normal mitochondrial function."

Working in collaboration with John Paul Glaves, a postdoctoral fellow in Bryan Sykes' lab, and Tao Huan, a PhD student in Liang Li's lab, Friis measured the molecules produced during the metabolic process. They found that the defective cells had higher levels of branched chain amino acids and trahelose, a carbohydrate found in yeast that can serve an energy source, similar to glycogen in human cells.

"By activating AMPK, we've removed certain blocks in metabolism. With the retrograde response, we've changed the amino acid metabolism in a way that allowed the cells to accumulate storage carbohydrates, which stabilize their function," Friis said.

Activated AMPK and retrograde response pathways allow the cell to accumulate a storage carbohydrate, which can be metabolize normally despite mitochondrial defects that affect the cell's metabolism. The additional energy stabilizes cell function and prevents premature cell death often caused by defects in mitochondria.

"No matter how many people are working on the problem in humans, mitochondrial disorders are too complicated to figure out the nuts and bolts without the work that Magnus is doing," Schultz said. "This research opens the concept, a new concept on how to deal with these metabolic problems."

University of Alberta Faculty of Medicine & Dentistry. "Manipulating the metabolic process in cells may compensate for defects that can shorten cell life." ScienceDaily. ScienceDaily, 11 April 2014. <www.sciencedaily.com/releases/2014/04/140411153852.htm>.

University of Alberta Faculty of Medicine & Dentistry. (2014, April 11). Manipulating the metabolic process in cells may compensate for defects that can shorten cell life. ScienceDaily. Retrieved March 3, 2015 from www.sciencedaily.com/releases/2014/04/140411153852.htm

University of Alberta Faculty of Medicine & Dentistry. "Manipulating the metabolic process in cells may compensate for defects that can shorten cell life." ScienceDaily. www.sciencedaily.com/releases/2014/04/140411153852.htm (accessed March 3, 2015).

More From ScienceDaily

More Health & Medicine News

Featured Research

Mar. 3, 2015 — Scientists have discovered a new hormone that fights the weight gain caused by a high-fat Western diet and normalizes the metabolism -- effects commonly associated with exercising. When tested in ... full story

Mar. 3, 2015 — New assays can detect malaria parasites in human blood at very low levels and might be helpful in the campaign to eradicate malaria, reports a new study. An international team led by Ingrid Felger, ... full story

Mar. 3, 2015 — Adults over the age of 30 only catch flu about twice a decade, a new study suggests. So, while it may feel like more, flu-like illness can be caused by many pathogens, making it difficult to assess ... full story

Mar. 3, 2015 — No significant change in home habits of smokers have been observed in the aftermath of a ban on smoking in public spaces, researchers report. Greater inspiration to kick the habit likely comes from ... full story

Mar. 3, 2015 — Heart function has been associated with the development of dementia and Alzheimer's disease through a new study. Participants with decreased heart function, measured by cardiac index, were two to ... full story

Mar. 3, 2015 — Children of recently separated or divorced families are likelier to drink sugar-sweetened beverages than children in families where the parents are married, putting them at higher risk for obesity ... full story

Mar. 3, 2015 — Gastric bypass and similar stomach-shrinking surgeries are a popular option for obese patients looking to lose weight or treat type 2 diabetes. While the surgeries have been linked to a decreased ... full story

Mar. 3, 2015 — Most people consume more salt than they need and therefore have a higher risk of heart disease and stroke, which are the two leading causes of death worldwide. But a new study reveals that dietary ... full story

Featured Videos

Mom Triumphs Over Tragedy, Helps Other Families

AP (Mar. 3, 2015) — After her son, Dax, died from a rare form of leukemia, Julie Locke decided to give back to the doctors at St. Jude Children&apos;s Research Hospital who tried to save his life. She raised $1.6M to help other patients and their families. (March 3)
Video provided by AP

Looted and Leaking, South Sudan's Oil Wells Pose Health Risk

AFP (Mar. 3, 2015) — Thick black puddles and a looted, leaking ruin are all that remain of the Thar Jath oil treatment facility, once a crucial part of South Sudan&apos;s mainstay industry. Duration: 01:13
Video provided by AFP

Woman Convicted of Poisoning Son

AP (Mar. 3, 2015) — A woman who blogged for years about her son&apos;s constant health woes was convicted Monday of poisoning him to death by force-feeding heavy concentrations of sodium through his stomach tube. (March 3)
Video provided by AP

Related Stories

Sep. 21, 2014 — Cancer cells traveling to other sites have different energy needs from their “stay-at-home” siblings, which continue to proliferate at the original tumor site, researchers have discovered. Given ... full story

Apr. 22, 2013 — The disrupted metabolism of sugar, fat and calcium is part of the process that causes the death of neurons in Alzheimer’s disease. Researchers have now shown, for the first time, how important ... full story

Sep. 2, 2011 — New research puts an unexpected twist on how mitochondria, the energy-generating structures within cells, divide. The work could have implications for a wide range of diseases and ... full story

Aug. 4, 2010 — Scientists have discovered that a group of proteins called IRPs ensure that iron balance is kept and as such are essential for cell survival. More specifically, they found that IRPs are required for ... full story

July 27, 2010 — Investigators have described a previously unknown biological mechanism in cells that prevents them from cannibalizing themselves for fuel. The mechanism involves the fuel used by cells under normal ... full story

ScienceDaily features breaking news and videos about the latest discoveries in health, technology, the environment, and more -- from major news services and leading universities, scientific journals, and research organizations.